nyoj1168An Easy Problem

An Easy Problem

时间限制：1000 ms  |  内存限制：65535 KB

难度：1

描述

    In this problem, you are given two integers L and R, and your task is to calculate the sum of all the number's square between L and R(inclusive).

输入

The first line contains an integer T, indicates the number of test case.
The next T lines, each line contains two integers L and R(1≤L,R≤10^5).

输出

Print an integer represents the sum.

样例输入

21 22 4

样例输出

5
29

简单的题目超时的时候多想想有没有数学公式可以解题

#include<stdio.h>int main(){int test;scanf("%d",&test);while(test--){long long a,b,sum;scanf("%lld%lld",&a,&b);if(a>b){int temp= a;a=b;b=temp;}printf("%lld\n",b*(b+1)*(2*b+1)/6-a*(a+1)*(2*a+1)/6+a*a);}}